Show:
What is a lens?
How do we see?
How eyeglasses work?
What is laser light?
Potpourri
100
Given an example of an Optical Device
camera, microscopes, projectors, telescopes
100
When light rays pass through the eye, the first eye structure that they come in contact with is...... A) cornea B) lens
A) cornea
100
In a normal eye the distance between the cornea and the ________________ is just right. A) lens B) retina
B) retina
100
Laser light is made up of how many colors?
one
100
A glass shaped like a wedge is called a ________________. A) Triangle B) Prism
B) Prism
200
This type of lens is thinner at the center then at the edge?
concave lens
200
When light hits the lens of the eye, the light is then........ A) reflected B) refracted
B) refracted
200
If the eyeball is too long or too short, the images that you see will be what?
out of focus or blurry
200
A laser light has how many wavelengths? A) many B) one
A) many
200
The distance between a lens and its focal point is called the what? A) focal length B) focal width
A) focal length
300
This type lens is thicker at the center than at the edge?
convex lens
300
Light rays converge exactly on this structure at the back of the eye. What is it?
the retina
300
Name the two types of blurred vision?
nearsightedness and farsightedness
300
Fill in the blank In a laser, the ______________ of all the wavelengths match up with one another.
crests
300
Why does our pupil expand in the dark?
To let in as much light as possible so we can see
400
A convex lens converges or focuses light rays. The place where those light rays meet or converge is called the what?
focal point
400
What happens to the light when it reaches the retina?
It is absorbed by the retina and transferred to the optic nerve, which then sends an electrical impulse to the brain.
400
Fill in the blank: A near sighted eye is slightly________ then normal. Light rays then converge at a point in_______ of the retina.
longer, front
400
Name one type of usage of laser?
Eye surgery, drilling and welding, barcodes, military applications
500
What does a concave lens do to light rays?
spreads them out
500
What happens to the lens when we are looking at something close up?
It changes focus and becomes stronger
500
How does a convex lens correct farsightedness?
Since the light rays are converging beyond the retina, the convex lens will make the light rays converge sooner on the retina.
500
Name one of the words in the acronym L.A.S.E.R?
Light Energy Amplification by Stimulated Emission of Radiation
500
How many cat's does Mr. Jensen have on the farm?
two